Scott DePutron
Julie Christman
Dr. Hasan
Dividing Polynomials Lesson Plan
Algebra 2
35 Students
2/7/12
80 minutes

Established Goals (Standards):
Common Core:
A-APR.1. Understand that polynomials form a system analogous to the integers, namely, they are closed under the operations of addition, subtraction, and multiplication; add, subtract, and multiply polynomials.

A-APR.6. Rewrite simple rational expressions in different forms; write a(x)/b(x) in the form q(x) +r(x)/b(x), where a(x), b(x), q(x), and r(x) are polynomials with the degree of r(x) less than the degree of b(x), using inspection, long division, or, for the more complicated examples, a computer algebra system.

A-APR.7. (+) Understand that rational expressions form a system analogous to the rational numbers, closed under addition, subtraction, multiplication, and division by a nonzero rational expression; add, subtract, multiply, and divide rational expressions.

California Math Content
3.0 Students are adept at operations on polynomials, including long division.

Learning Objective:
Students will be able to:
  • Divide polynomials using the methods of long division and synthetic division.

Key Ideas:
  • Long division
  • Synthetic division

Essential Questions:
  • What are the steps used to divide polynomials using long division?
  • What are the steps used to divide polynomials using synthetic division?

Academic Language:
  • Monomial, binomial, trinomial, polynomial, numerator, denominator, dividend, divisor, quotient, remainder, terms, degree, FOIL, coefficients, “like terms,” factor, GCF, difference, sum, product, variable

Key Academic Genres:
  • Polynomials
  • Rational Expressions

Needed Materials:
  • SmartBoard notes
  • Whiteboards
  • YouTube video
  • Group chart

Lesson Activities:
  • Warm-up Video (Mr. Duey)
  • Vocabulary Review
  • Warm-up problems
    • o Long division
    • o Dividing Polynomials by a Monomial
    • Dividing Polynomials by Binomials
    • Pair Activity
    • Group Activity
    • Group Inquiry-Exploration
    • Reflection (What did we learn?)

Assessments:
  • Informal:
    • o Whiteboard answers
    • o Answers to classroom questions
    • o Group interactions
    • o Group answers
    • Formal:
      • o Class Presentations of Problems
      • o Homework Review Quiz
      • o Homework Presentations

Problems that the students will be doing:
3. (27x4 - 18x2 + 9x) ÷ 9x
4. (x2 + 12x - 160) ÷ (x - 8)
7. (21x2 - 29x - 10) ÷ (3x - 5)
10. (4x3 - 7x + 8) ÷ (2x - 1)

Other ways students might solve these problems:
  • Students may set up the division vertically and attempt to cancel terms or use the method of long division.

Misconceptions and challenges might students have:
  • Students may not divide each term in the numerator by the denominator.
  • Students may cancel out exponents from solely one term in the numerator with one term in the denominator rather than distributing the whole denominator to each term in the numerator.
  • Students may not distribute the negative sign to the whole binomial when subtracting in long division.
  • Students may forget to use placeholders for missing terms when using long division.
  • Students may not remember the steps involved when the remainder is not zero.
  • Students may not bring down the first term before following to multiply and add when using synthetic division.

Extension Activities:
  • Dividing Polynomials HW 1
  • Introduction to synthetic division in following lesson.